Canadian Institute for Historical IMicroraproductions / Institut Canadian da microraproductions historiquas
Technical and Bibliographic Notes / Notes technique et bibliographiques
The Institute has attempted to obtain the best original
copy available for filming. Features of this copy which
may be b[bliographically unique, which may alter any of
the images in the reproduction, or which may
significantly change the usual method of filming are
Coloured covers /
Couverture de couleur
Covers damaged /
Covers restored ind/or laminated /
Couverture restauree et/ou pelliculee
Cover title missing / Le litre de couverture manque
Coloured maps / Carles geographiques en couleur
Coloured ink (i.e. other than blue or black) /
Encre de couleur (i.e. autre que bleue ou noire)
Coloured plates and/oi illustrations /
Planches et/ou illustrations en couleur
Bound with other material /
Relie avec d'autres documents
Only edition available /
Seule edition disponible
Tight binding may cause shadows or distortion
along interior margin / La rellure serree peut
causer de I'ombre ou de la distorslon le long de
la marge inteneure.
Blank leaves added during restoratK>ns may appear
within the text. Whenever possible, these have
been omitted from filming / II se peut que certaines
pages blanches ajoutees tors d'une restauration
apparaissent dans le texte, nrais, k>rsque cela ^tait
possible, ces pages n'ont pas 6te film^es.
Additional comments /
L'Institut a microfilme le meilleur examplaire qu'il lui a
ete possible de se procurer. Les details de cet exem-
Dlaire qui sont peut-etre uniques du point de vue bibli-
Dgraphique, rjui peuveni modifier une image reproduite,
ou qui peuvent exiger une modifications dans la meth-
ode normale de filmage sont indiques ci-dessous.
I I Coloured pages / Pages de couleur
I I Pages damaged / Pages endommagees
I I Pages restored and/or laminated /
' — ' Pages restaurtes et/ou pellKulees
Fy] Pages discoloured, stained or foxed /
' — ' Pages decolorees, tachetees ou piquees
I I Pages detactied/ Pages ditachees
l~y Showthrough/ Transparence
I I Quality of print varies /
' — ' Qualite Inegale de I'impression
I I Includes supplementary material /
— Comprend du materiel supplementaire
I I Pages wholly or partially obscured by errata
' — ' slips, tissues, etc., have been refilmed to
ensure the best possible image / Les pages
totalement ou partiellement obscurcies par un
feuillet d'errata, une pelure, etc., ont m filmees
a nouveau de fa;on a obtenir la meilleure
I I Opposing pages with varying colouration or
' — ' discolourations are filmed twice to ensure the
best possible image / Les pages s'opposant
ayant des colorations variables ou des decol-
orations sont filmees deux fois afin d'obtenir la
meilleur image possible.
This ittm is filmid at th« rtduclion ratio ehtcktd btlow/
Ce docuffltnt est filme au tauK de rMuction indique ci-dessous.
Th* copy filmed h*r« hu bMn raproducad thank*
to tria ganaroaiiy of:
National Library of Canada
L'aiiamplaira film* fut raproduit grica * la
Bibliotheque nationals du Canada
Tha imagaa appaaring hara ara tlia bait quality
pOMlbIa eonsidaring tha condition and lagibility
of tha original copy and in kaaping with tha
filming contract apacificationa.
Lat imagat auivantaa ont M raproduiias avac la
plua grand toin. compta tanu da la condition at
da la nattat* da I'axamplaira filmt, at an
cenformit* avac laa condition* du central da
Original copiaa in printad papar covars ara fllmad
baginning with tha front covar and anding on
tha laat paga with a printad or illuatratad impraa-
sion. or tha back covar whan appropriau All
othar original copiaa ara filmad baginmng on tha
firat paga with a printad or illuatratad impraa-
sion. and anding on tha laat paga with a printad
or illuatratad impraaaion.
Tha last racordad frama on aach microfieha
shall conuin tha symbol -n» Imaaning "COfJI-
TINUED"). or tha symbol ▼ Imaaning "END I.
Maps, platas. charts, ate. may ba filmad at
diHarant raduction ratios. Thosa too larga to ba
antiraly includad in ona amposura ara filmad
baginning in tha uppar laft hand eornar. laft to
right and top to bottom, as many framas aa
roquirad. Tha following diagrams illustrata tha
Laa axamplairaa originaux dont la couvanura an
papiar aat Imprimaa sont H\m*» an commancant
par la pramiar plat at an tarminani soit par la
darni*ra paga qui comporta una amprainia
d'imprassion ou d'illustration. soit par la lacond
plat, salon la caa. Toua laa auiras axamplairas
originaux sont fllmaa an commandant par la
pramiAra paga qui comporta una amprainta
d'impraaaion ou d'illuatration at an tarminant par
la darniira page qui comporta una talla
Un daa symbolaa suivants apparaitra sur la
darni*ra imaga da chaqua microfieha. salon la
cas: la symbola — » signifia "A SUIVRE", la
symbola V signifia "FIN".
Las cartas, planchaa, ubiaaux. ate. pauvant aira
filmto 1 daa Uux da reduction diff*rants.
Lorsqua la documant ast trop grand pour aita
raproduit an un saul clich*. il asi film* * panir
da I'angla supariaur gaucha. da gaucha * droita.
at da haut an baa. •n pranant la nombra
d'imaga* n*caa**ira. La* diagrammaa suivania
illuatrant la matheda.
1 2 3
1 2 3
MICBOCOPY RESOLUTION TIST CHART
lANSI ond ISO TEST CHART No. 2)
1^25 ji 1.4
On Wire Ropes.
By W. I). 1,. llAKi.m, M.l'., I.elhliriiiKe, Alta.
That wire rope as a mechanical means of cheaply conveying coal
IS being superceded by electricity and comijrcssed air is not admitted
by many mining engineers.
After many years of careful study of lb-.' three systems ano closely
watching the actual application of the •. all, we are fully convinced
that wire rope haulage will live on after some of the new fangled
systems have settled down to their proper sphere. That compressed
air and electricity have many advantages in some respects, it is not
our purpose to controvert, but that wire rope haulage actuated by
steam, electricity or compressed air has a wider field than either the
compressed air or electrical locomotive is our contention. If
this be admitted as correct and, whether or no, it certainly is the
duty of all mining engineers and colliery managers to have as
complete a knowledge about wire ropes as is possible in one having so
many diversified duties to p'-rform, so that he will not be entirely at
the mercy of the rope manufacturer who has his little " trick of trades "
in common with most other manufacturers.
It is the writer's intention in this short |iaper to give some practical
and theoretical notes on wire ropes, not claiming any originality, in
the hope that they may be beneficial to the younger members of the
Wire ropes for mine use are generally composed of :
(i). Six wire strands composed of s»ven wires each, twisted on a
hemp centre. 1 ne centre wire of the st' Mid sometimes being soft.
(2). Six wire strands composed of twelve wires each, twisted on a
(3). Six wire strands, composed of nineteen wires each, twisted on
a hemp centre.
This construction is sometimes varied so that there are 13 larger
wires and 6 smaller wires in each strand, but the general construction
of the rope is the same.
' The Canaiiian Mining Imtilute.
The ratios of the diameter of the individual wires to the diameter
of the rope in these three cases, not including the rope with two sized
wires as in No. 3, are as follows : (,) ., (,, ;^., (3, ,,.. prom this,
the gauge of wire required to conFtitute a rope can readily be got to a
No. I is only used where large wheel drums and easy curves
can be employed. Such a condition does not very often present itself
in coal mines. The No. .. rope is a more pliable one and can be used
on smaller drums, wheels, and curves, Imt when we remember that the
size of tlie individual .vires govern the si/e of wheel it will be seen that
with this rope, with a heavy load, such as is usual in mine haulage,
the wheels would be relatively large. \ wire shouM not be bent over
a wheel less than .,000 times i;s diameter for good lesulis in length of
life and tons hauled.
Excepting in ropes of large diameter No. 3 is not used for mine
haulage but is largely em])loyed for hoisting ropes.
To meet the conditions of severe bending usual in the underground
working of collieries the British manufacturers construct a compound
rope which we will designate as (4) :
(4). Six wire strands, each composed of 9 large wires twisted
around 7 smaller wires (the centre or seventh wire being soft), twisted
round a hemp centre. The gauges of wire used and number of wires
used in the construction of a compound rope are varied to suit the
circumstances. These ropes are very servicable and meet the mine
manager's wants with a wonderful degree of satisfaction.
I am not aware that any American rope makers are constructing
ropes of this style.
In computing me strength of any twisted wire rope it is well to
remember that the strength of each individual wire is reduced from
4 per cent, to ,0 per cent, by twisting. The makers claim the strength
IS reduced 4 per cent, while disinterested experimenters claim the
strength is reduced .0 per cent. Perh.aps a fair allowable reduction
of strength for twisting in manufacturing, would be the average of the
two, viz : 7 per cent.
Iron wire rope.5 are not suitable jr mining purposes and are not
considered in this paper.
■♦■ Tsss^^ srsn"*"*"-
Oil IViir Kofes.
There is a very wide ranfje in the grades of steel ropes and as tlie
breaking strengtii per s(|iiare inch of section of ihe material of ivhicli
they are constructed is fundamenial, we herewith give a short tahle
which will make the point clear.
r<l oi Cnii-il.lc Slul.
■r.iii. tmiis r,,!!,. ]■,,
The ipiality here is in tons of 2,240 lbs. per square inch of
The composition that enters into these grades is partly a secret of
the manufacturer, however, a vast amount of information has been
published but the articles are too numerous and conllicling to he
brought within the limits of this paper.
For the purpose of making the above tables clear let us take an
example: -Suppo.se we are going to use a crucible steel rope is-ifi
inch diameter, or 3 inches circumference, composed of six strands, each
strand having 9 wires .080 inch diameter, twisted over 7 wires .054
inch diameter, of 201,600 lbs. breaking strain per square inch, what is
the breaking strain of the rope .^—
.082 in. X .7,854 .\ 201,600 lbs.= 1008" X9 wires. 9,.)72 lbs.
.0542 in, X .7,854 X 201,600 lb5.= 4fii.7'-x6*wire.5. 2,77olbs.
of one strand 1 ,,,S42 Ihs.
11,842 lbs. X 6 strands ■> 1,052 lbs.
Less 7 per cent, allowed for twisting 7,105 lbs.
Breaking strain of rope 63,947165.
t The safe working load in underground haulage
may be from 1.7 to 1-5 say 1-6 10,658 lbs.
* Six of the seven small wires only enter into this calculation as
the seventh wire is the core of the strand and is soft having little
Thf Oinadian AfiiiiHg Imlilule.
t A rope running at a low speed and no lives depending upon it, is
not subject to the sudden strains ol' a high speed rope and may have a
very low nicior of safely. In slow endless rope haulage i-j miles per
hour, we iliink, •; is a safe factor. Hut with fast running tail-ropes 7 is
not toil ,irge. For hoisting ropes the safe factor should be 10.
The following we regard is a good sample of a specification for
wire rope : —
Qiiiirv iif mir.—i. All steel used in ihe manufacture of the
cable shall be of 1 he "best scleclcd i)atent in-iiroved crucible steel"
drawn to a uniform diameter throughout, and ■:a,,..ble of withstanding
the lists tncntioned in the table given bcljw.
r.iiij;l/i, in,' anu'/orm 0/ H^'h,- 2. The c.ule shall be
feet long ..id shall have a circumference of 35 a inches (three and
five eighths) when finished. It shall consist of six outside strands laid
u]) in the formation known a^ the '■ Lang lay," with Ihe lay in the rojie
in the same direction as the lay in the strat.Js.
Stiaiidi. — T,. Each strand shall he composed of seven wires .115
mch in diameter, laid round a core consisting of five wires .061 inch
in diameter round one wire .049 inch diameter.
Spinning.— ^. Kacli strand shall be spun in feet lengths and
evenly woimd ilirect from the machine on to a reel. When it is
necessary to join either tne outside or inside wires they sh.all be pro-
perly scarfed and brazed.
Chsing.—^. The si.x strands shall be closed under i.iiform tension
round a heart consisting of the best white manilla rop», having three
strands, hard laid, and well soaked in oil.
l,iy.—6. The lay of the wires in the strands shall le 53,| inches
(three and three-quarters) .ind the l.iy of -he strands in the cable y'/,
inches (nine and one half).
On IVire Kcfrt.
TABLKS OF TKSTS- 7.
UiiKthof let, T*-"!*'!* l«t. i
piece betwreii , Streai
gauge itiark*. Mr*M per per wire,
H inchei .
Here Ihe core wire of the slrand is not soft as in the case we
made the calculation for.
Lingth of tMt,
B^nds to IS<)°
radi Hank to be siiUfclcd to t,-sl.—%. Uefore proceeding with the
manuacture of tne cable, the contractor shall submit every ha nl. of
wire to the engineer, who wii: make tensile and ductile tests from each
end of the hank before it is worked into the cable.
ya,i,itim from sptcified trsls.—g. Kvery hank wiiich shall be
found to vary more than 2'/, |,er cent, in either direction from the
tensile tests specified above, or more than 8 per cent, below the
specified number of twists in 8 inches will be rejected.
Test of Call/,:— to. The contrac'or shall make the cable suffi-
ciently long to allow for cutting off a suitable portion which shall be
lested for tei sile strength in the jiresence of the engineer, or his repre-
sentative, and must withstand a load of 4.? tons (ton here is 2,240 lbs.)
Costof making tests.— II. The cost of all tesis, whether made at
the contracto '- »n-ks or elsewhere, shall be borne by the contractor.
iHe Omadian Mining Institute,
Otrmi^^ii t.it\.—\2 In addition to (he aliovc, rhcmicil tcstH may
iif made at ihu liHcretion oj the engineer.
t nitir wire.
MS in. <lititii.
.(i.l<) In. Hiani
"Manganese imparls loiiijiincss and nculraiiscs •■shorlness," it
furlhcr acts in favor of il.c presence and functions of the carlmn."
Silicon can only Iw tolerated in very limited riuantities, wliilst jihos-
phorus and sulphur are the greatest enemies encountered in the
manufacture of steel. Any excess of silicon produces brittleness,
wliich is more marked as the percentage of carbon is raised. Small
■ luantities of sulphur present in steel will produce unsoundness and
"red shortness" whilst phosphorus is detrimental on account of
causing " cold shortness " besides being an enemy to any form of
tempering and conductivity."— iw/M.
In the ordinary construction of wire rojies the wires forming the
strands are twisted to the left hand but the strands are tivisted to the
right hand, or opposite direction. In die " I.ang lay " the wires form-
ing the strands and the strands comprising the rope are all laid in the
same direction. Ropes may be laid up "right" or "left" hand and
this is no small consideration in the life of a ro|)e if one coil chafes on
another. If, when standing behind the drum facing the pit head
pulleys, the rope travels on drum from left to right, the rope should be
laid "right handed," or vice versa. The tendency 10 mount and side
friction are miiiimised.
The "lays" adopted in wire rope inaking are principally dependent
upon the gauge of the wires em]>loyed, the size of the rope to be made,
and the purposes they are intended for. .Approximately it may be saiti
that the "lays" in strand, vary about ihree to four times the diameter
of the rope and the " lays" in the rope vary from seven to ten times
the diameter of the mpe.
The average elongation of ordinary constructed ro|)e is about
.3 percent, and with "Lang lay" ,'/, percent, to j per cent, which
On lliir A'k/vs
mint not l« lo.t sight of in hoisting rope> and endless rope. ,\ ,,„,.
able tiKhtcning arrangement wii] take up ihf elongation in endless ropes
but in hoisting ropes it is a case of pullinj, t .e rope up in the fasten-
ings in the drum.
With hoistinn rop.i ihe life can be greatly i,„ reased by ordering
sufficient length to enable 6-10 feet to be cut off the end periodically
and thus change the point of lift or stress.
It IS of ih. rsi importance th:it ropes be greased i- . uently and
carefully with ., good, pure, grease which is absolutely u.^ rom acids.
A greab^' with acids in it is worse ihan no grease.
I is obvious where ropes have to bend round wheels, drums, or
cf • 's, that the outer fibres of ,„».', win; as they accommodate them
selves to the curvature, are in tension, and the inner wiies in com
pres-sion, whiL the center or neutral axis is unchanged. As a con-
sequence it may be assumed that ihe more Hexible a rope, ,. ,-. offers
less resistance in compression and tension in each wire, where it is
subjected to much ,inding in work, the belter will be the results, pro-
vided that such f bilily be not obtained by the use of such line wires
that the wearing capacily of the rope is affected.
We said in the early |)art of this paper that a rope should not
bend over a wheel less than .,000 ties the diameter of the largest
individual wire in the roi>e. This 'niili up on a.suming .S ._ 30.000
from which we have U = .10,000,0c . d = 1,000 d. This only implies,
afur all, that if 1) is greater than 1.000 d the life of the rope will be
greater and ria- :rrsa.
A prominent rope-maker in Kngland answers a letter of enquiry
from us asking his rule by which to calculate the siie of wheel for a
given size of rope as follows :—
'• In haulage it is advisable to u.se the larg :si pulleys vou can
possibly get in; this however is governed a great deal'by 'the con-
ditions under 4vhich you have 10 work, and when we know the sue of
the pulleys you are using we can generally suggest to you the class of
rope most suitable. There is no rule for this, but it is purely a matter
of experience and how ropes have worked under similar conditions in
The Canadim, Mimng InUituU.
E= Modulus of e;ast/rit» ...i,; u ■ U
can U 30.cco,ooo. pounC'r^^.e •„:! ^■■"""^- ^'^ ^'"' ^ -"
d — Diameter of a sinele wirp nf .h-
D_= Diameter of pu4;~:'''"''^ ■"■-''"■
-^i^e ofThe'lTer;::: '■"^'' '''"^"°" -- -<^ "P™ -^^ oute™„«
-^e'rS:^:-::;^J-f-.;''e diameter Of .e outer
-e on,, for conveni^ce^eCd -°:8""": ""■""" °' -■- ("ere
S ^ JL = 30,000,000 .08 inch ~, "„'"' " = «° '-''"•
j^ -uo men -_ 30,000 lbs.
.„, 80 inches.
ihe cross sectional area nf ih. .
ample is:_ * °' ">' '"^ ^'^es of wire in that ex-
•35388227 X 30,000 lbs = ,„fi ,; ,u -35388227
The stress produced on ,J, ^^ '""' ''"^ '" lending,
^idered in conne'ction ^W. h h ' ,"::'™ T 1 '"""'"'' ">-' "--
a-ve a. the total stress. iV:;;"''""^''^ ''>^ '-d in order .0
-^a..at.hesum Of these t.o sir iirr:::::;!:
"TiTtJT" 3 + safe factor.
On Hire Ropes.
lut of the
= K d^
In the example the factor 6 was allowed to overcome bending
stress, sudden jerks, etc. By finding the bending stress we see that
factor a of 3 is ample to pnt up for the other possible stresses. .^
threefold security is considered sufficient.
Whatever may be the relation of these two stresses, pulling and
bending, the total stress on the rope will be that due to the com
bination of these two stresses.
If D is made so small that the two stresses, pull and bending, are
greater than the clastic limit the rope will receive a permanent set
which, however, is not always dangerous.
In this connection we might call attention to the baneful effect
attending the use of wire ropes where reverse bends are made. Care
ful record and e.xperiment have shown that the life of the winding rope
which goes over the pit-head pulley and under the drum is only from
one-half to three-quarters as great as the rope which goes over the pit-
head pulley on to the top of the drum.
The importance of greasing ropes is also accentuated by Mr
Biggarfs tests. Two lengths of the same size and manufacture of rope
were used; the unoiled length made only 16,000 wherea.. the oiled
length made 38,700 bends over the same pulley before breaking.
Other similar pieces of rope unoiled would run over a 24 inch pulley
74,000 times, and the oiled length 386,000 times.
This paper has assumed proporiions we had not intended when
undertaking its compilation, and indeed it has been compiled on lines
that wc had not intended when commencing it. Such a paj.er as this
cannot be considered complete without considering many other im-
portant points in wire rope construction, and its use, such as the
neutral axis, the proper diameter of sheaves, curves, etc. At some
future time we may send in another paper covering these important